This invention relates to a multi-component offshore platform and to a method for erecting the same.
Heretofore, piled steel platforms and concrete gravity platforms have been devised for offshore use. However, as it becomes desirable to locate offshore platforms in still deeper water and in more hostile environments, the piled steel platforms and concrete gravity platforms have been met with severe challenges. At the present time, in the sizes now available, the capabilities of the industry are already being strained to the limit, not only in construction but also in the transportation, launching, and installation of these structures. A tremendous increase in their size will be required as the water depth and the severity of the environmental conditions are further increased. This size increase will not only add considerably to the already tremendous structural cost, but will exceed the existing capabilities in almost every area related to design, construction, and installation of these very large offshore structures.
An object of the present invention is to make it possible to locate offshore platforms in still deeper water and still more severe conditions. The invention employs a system in which the base supporting structure is spread over a much larger area by using components that are attached to each other.
Other objects of the invention include making more feasible and more economical the building of such platforms in deeper water and to make them better able to withstand more severe environmental conditions. Severe conditions such as earthquakes, ice forces, and unusually strong winds and large waves can be withstood better by employing the system of the present invention.
A further object is to accommodate differential settling of some elements with respect to others.
A still further object is to provide a novel interior oil storage structure.